| 摘要 |
PURPOSE:To prevent the formation of voids, pinholes in inside and outside parts of a molded product, by avoiding direct contact of molten resin to the tip part of a lead frame protruding in a cavity for resin molding between upper and lower molds, pressure-injecting it to a bottom face side of said cavity. CONSTITUTION:Step parts 1a, 2a in vertical direction are shaped in a neighboring part of a wall face of a cavity 3 at both molds 1, 2, also a gate 4 provided to the upper mold 1 side is constituted to connect and open at a position so as to be at the almost same level as the bottom face 3a of the cavity at the lower mold 2, and molten resin 7 is pressure-injected from the bottom face 3a side of the cavity corresponding to a lower face side without touching a tip part 6a of a lead frame 6 directly. In such a way, molten resin poured in the cavity does not cause turbulent flow, air entrapping is hindered and formation of voids, pinholes in molded products is prevented. |
